The main objectives of this project are to evaluate the effects of immunologic manipulation on the time of appearance and the incidence of radiation in chemically-induced tumors, and to determine the effect of age at the time of irradiation. Subsequently, we are attempting to determine the effects of immunologic manipulation on the radiation responses of tumors. Our present plans are to complete our present carcinogenesis experiments with immunosuppression and immune stimulation utilizing MSFMB (methanol soluble fraction of Mycobacterium Butyricum); also, completion of our analysis of radiation carcinogenesis studies and preparation for future publication.